Trick Flow small block heads

if you go by TrickFlows numbers they say 281@.500 and 248@.400 lift. by time you take pushrod deflection and the dreaded small block pushrod angle how long do you think that "dinky" cam is spending at .500 lift. Not very long.
I agree. It seem most people talk about flow at max lift but how long is the valve open at max lift. About a microsecond? Nanosecond? What's more important is flow where the valve is open the longest, sometimes referred to as "area under the curve." It's interesting that the racer boys at Mopar would recommend a .750 lift cam for a big block with stock heads when the heads stopped flowing at .670! It was because the heads didn't' stall after .670 lift and the big cam provided a lot more duration in the area where the heads flowed the best.